Stereolithography (SLA), selective laser sintering (SLS) and selective laser melting (SLM) belong to the group of generative manufacturing methods and are also generally also referred to as “3D printing methods.” In this case, data sets are generated on the basis of geometric models, which data sets are used in a special generative manufacturing system for producing objects having a predefined shape from amorphous materials such as liquids and powders or neutrally shaped semi-finished products such as band-shaped, wire-shaped or strip-shaped material by means of chemical and/or physical processes. 3D printing methods use additive processes in which the starting material is built up sequentially in layers to form predetermined shapes.
3D printing methods are currently widely used in producing prototypes or in rapid product development (RPD), in which a resource-efficient process chain is used for small-scale and large-scale series production, as required, of individualized components. 3D printing methods have various uses in civil engineering, in architecture, in dental technology, in toolmaking, in implantology, in industrial design, in the automotive industry and in the aerospace industry.
3D printers, and in particular laser sintering devices, use both a computer-aided construction system (computer-aided design, CAD) and a beam system which carries out the generative layer construction of the object to be printed on the basis of the digital manufacturing model provided by the CAD system. A three-dimensional CAD model of the object to be printed undergoes a preparation procedure here which is carried out in order to generate the control data required for the beam system and is known as “slicing.” In this process, the CAD model is digitally broken down into layers of a predetermined uniform thickness having layer normals in the construction direction of the beam system, which layers then form the basis for controlling the beam of energy on the starting material surface in the beam system. A conventional layer breakdown algorithm constructs the CAD model on an inlaid surface model in this case, which results in a number of closed curves or surface polygons which define the “slices” between two model sections which are in succession in a manner perpendicular through the construction direction of the beam system.
Surface models of this kind can be stored for example in STL format, which is conventional for stereolithography and which describes the surface geometry of the three-dimensional object to be printed in the form of raw data having unstructured triangle textures. The beam system reads the surface model data and converts the data into a corresponding control pattern for the laser beam in an SLA, SLS or SLM manufacturing method.
3D printing methods such as SLA, SLS or SLM result in significant design freedom in terms of geometrical shape and structure when manufacturing complex three-dimensional components. In this case, it is desirable to accelerate the manufacture of components by carrying out manufacturing steps more efficiently.
Various approaches in the prior art deal with 3D printing processes that are based on a rotational movement of construction platforms: DE 10 2013 210 242 A1 discloses a system for selective laser melting using a pot-shaped powder-bed support which can be rotated during powder-bed production. DE 10 2009 046 440 A1 discloses a device for the generative production of a component, comprising a lowerable support plate and a material supply unit rotating above the support plate. DE 102 35 434 A1 discloses a device for the layered, generative production of three-dimensional objects, comprising a rotatable construction region. US 2008/0109102 A1 and US 2004/0265413 A1 each disclose a 3D printing device comprising a rotatable construction platform. WO 2015/139094 A1 discloses a computer-controlled system for the generative manufacturing of components, which comprises a robotic arm that is mounted in a hardenable liquid and comprises a construction platform mounted thereon so as to rotate and tilt.